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Comfrey again.

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Problems:

The myth that comfrey is completely benign just won't die.

It's popped up again on a mailing list I'm on. A list member lamented the fact that the FDA (or suchlike) has banned the plant ... here's my reply.

That's because comfrey contains livertoxic pyrrolizidine alkaloids.
Which directly cause veno-occlusive liver disease.
Which is silent, until your liver is fried.

Comfrey (Symphytum officinale and other species) had been considered safe because the onset of liver problems is so slow that you couldn't really connect the disease to the plant. Also, they didn't do liver autopsies all that often, half a century and more ago. Nowadays, liver autopsies are a tad more common; in addition, there's the possibility of doing a liver biopsy - same as an autopsy, but on live people. Autopsies and biopsies do prove that yep, comfrey is toxic.

Comfrey has necessitated a handful of liver transplants over the last two or three decades. Those are the ones where comfrey was known to cause liver failure. There might be more, and of course, there might be a few deaths due to liver failure due to comfrey livertoxicity.

This toxicity of comfrey has been known since the mid 1980s. Any herbal people who still insist that it's completely benign don't know what they're talking about.

Another herb which contains livertoxic pyrrolizidine alkaloids is coltsfoot (Petasites hybridus and other species, and Tussilago farfara). Of these, Petasites has killed a baby, cos mom drank the tea for her cough ...
Stay away from all and any of the plants which contain livertoxic pyrrolizidine alkaloids, especially if you're pregnant or nursing.

The Germans are perhaps sanest about these toxic alkaloids, and suggest that you might drink Tussilago (but not Petasites) tea for a few weeks every year. You'll find their suggestions for European herbs here.

Note, there are also nontoxic pyrrolizidine alkaloids. Echinacea is an example of a plant which contains completely benign pyrrolizidine alkaloids.

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Instead of comfrey, try calendula or plantago - both of these are extremely good tissue healers. Add one or the other high-silica mineral herb like horsetail or the green parts of oats to that, and you've pretty much emulated comfrey's healer + minerals qualities.

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Related entries: Livertoxic PAs - Coltsfoot toxicity

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Comments are now closed.

Comments

My understanding, from reading articles in scientific journals is that the pyrolizidine alkaloids are found only in comfrey root, not leaves. Could you comment on this?

You'll find them in both.

Then there's the story that Susun Weed had S. uplandica mature leaf tested and there were no PAs in it. Her take on it, I think, is that the garden comfrey (purple flower) has little or no PAs in the leaf, but to avoid the wild comfrey (yellow flower) should be avoided. She also suggests not using young leaf.

It'd be good if some really good research was done on comfrey, that takes into account species, form, location, use etc. Unfortunately at the moment we have a handful of stories about liver failure (which I've also read), and a handful of stories of long term use with no problems.

I do agree that it's important to look at comfrey and make informed decisions rather than just going oh it's totally safe.

That's very nice. Now, how much PAs were in that comfrey in spring? Full summer? Fall? How much in the young leaf? Old leaf?

Until you've tested it in a lot of circumstances, you can't say that it's free of livertoxic PAs.

(And I don't really believe Symphytum x uplandicum to be PA free -- it's a hybrid of garden comfrey (Symphytum officinale) and prickly comfrey (Symphytum asperum), both of which contain livertoxic PAs.
Neither does Professor Roeder, who tested the plant: "4.1.12. Symphytum x uplandicum ... A total alkaloid content of ca. 0.2% was found in the dried aerial parts [90, 91, 139, 140]. Russian comfrey should no longer be used for medicinal purposes.")

Next, garden comfrey comes in two colors ... light yellow and purple.

Then, about those "handful of stories of long term use with no problems": when did these people have their last liver biopsy? Because if they haven't had that done, they have no idea if comfrey is damaging them or not ... until their liver is fried.

And go read the PA article, it's fairly substantial.

"Until you’ve tested it in a lot of circumstances, you can’t say that it’s free of livertoxic PAs."

Yes, that is why I'd like to see some good research.

I'm not contesting your concerns, in fact I point people in the direction of your writings on comfrey and PAs when I hear the 'it's totally benign' line.

Myself I tend to sit in the middle somewhere*. We know that science research on herbs is often severely limited. Comfrey is such a useful plant that I'd like to see some comprehensive research done.

*mainly because I think that comfrey has been used so much that even within the short history of liver biopsying we'd be seeing much more evidence of a problem if most people who used comfrey got liver damage. It seems likely that there are some mitigating factors, and I'd like to know what they are.

Maybe they could do some studies on people with veno-occlusive liver disease and check for comfrey use.

"Next, garden comfrey comes in two colors … light yellow and purple."

That's the problem with common names. Thanks for clarifying about the uplandica hybrid, I've never been sure exactly what it was. Weed refers to the yellow flowered comfrey as 'wild'.

The last link you gave is broken. [fixed now, thanks!] I've read your posts on PAs before :-)

I do like Jim's suggestion that Susun donate her liver for biopsy.

Anybody who distinguishes comfreys by flower color has no idea what comfrey they're actually looking at. Most of them are purple, garden comfrey (and creeping comfrey) can also be light yellow (or even striped light/dark pink), only one of them is bright blue, and so on.

What counts, with comfreys, is the form of the flower (and how the leaf attaches to the stem, and height, and so on). Botany. It's likely useful on a number of fronts, if you're into plants. Of course, it's muddled quite a lot by the various comfrey hybrid swarms ...

"I do like Jim’s suggestion that Susun donate her liver for biopsy"

Yes, that is among my more brilliant notions. Perhaps someone could suggest it to her? I've met her but don't really know her, and I do think that if you're suggesting what someone should do with their organs they should know them a bit better than simply from having taught at a weekend event with them once...

But susun's liver would probably not be enough to give the issue a fair shake, perhaps a wise (wo)man comfrey infusion liver drive would be in order? Maybe we could coordinate with the DMVs and Secretary of states to add a PA Liver Biopsy option to the back of drivers licenses...

Do you EVER use comfrey leaf in your balms/salves? I know the root contains more of the liver toxic element than the leaf. Can the body still get liver damage from using a salve/balm made with the leaf? Assuming a person uses it daily..........like for a rash or diaper rash, or a scrape.
Thanks for repeating what you have said over and over.

No, I don't use comfrey externally either. The pyrrolizidine alkaloids don't get in through whole skin (so it's good for sprains and things), dunno about broken skin though.

This controvery about PA's for comfrey makes me wonder what *other* plants have PA's (or kidney toxins, ect) that we really don't know about yet.

I rely on my intuitive when in doubt (combined with education) to make the decision on herbal use or just a visual appreciation mode....I love my borage patch, for instance, but I only love it in my garden for it's beauty and as a bounty for the bees. I just have never felt like I should really *
use the plant internally. Yeah, I've read up on all the great uses for borage flowers and borage leaves for soup for years...I probably review borage herbalism info once per year. I just for some reason never felt like going there.

I'm ok with that though since I am with you Henriette in your thinking that there are SO many greatly studied non-controversial plants - plants that FEEL good and correct to me as well - that I don't need to stress out about using plants that I may not understand how to use correctly.

And ...as a professional gardener/ horticultural enthusiast, I think it is perfectly fine to simply admire some plants and imbibe their energy pattern from a distance rather than bodily in any way!

No, I don't use comfrey externally either. The pyrrolizidine alkaloids don't get in through whole skin (so it's good for sprains and things), dunno about broken skin though.

If the alkaloids don't get in thru whole skin, then why don't you use it externally?
Say for a diaper rash, or scrapes that are closed up? Is it you just don't want to take the chance?
Thanks much for your anticipated reply.............:)

WELL I DONT KNOW MUCH ABOUT THE TEST DONE ON COMFREY,BUT I DO KNOW QUITE A FEW PEOPLE THAT HAVE USED COMFREY BOTH EXTERNALLY AND INTERNALLY AND NOT ONE OF THE ONES I KNOW HAVE PROBLEMS FROM IT.AND BEFORE YOU MAKE THE COMMENT ABOUT HAVING THEIR LIVERS TESTED.WELL ONE LADY I KNOW IS 85 YRS OLD AND HAS BEEN EATING COMFREY SINCE SHE WAS A BABY AND IF THE COMFREY WAS GOING TO CAUSE LIVER PROBLEMS I CAN TELL YOU IT WOULD ALREADY HAVE HAPPENED.BY THE WAY SHE IS A VERY HEALTHY AND SPRY 85 YR OLD AND HER MOTHER WHO ALSO ATE COMFREY ALL HER LIFE JUST DIED AT 99 YRS OLD OF A HEART FAILER AND HAS NEVER HAD SIGNS OF LIVER PROBLEMS AND YES SHE DID HAVE A LIVER BIOPSY AND IT WAS NEGATIVE.I ALSO KNOW PEOPLE THAT HAVE FED COMFREY TO THEIR CATTLE AND PIGS AND WHEN SAID ANIMALS WHERE BUTCHERED FOR FOOD THEY HAD NICE HEALTHY AND DELICIOUS LIVERS.I JUST THINK IF YOUR GOING TO SPREAD THIS INFORMATION YOU SHOULD GET MORE FACTS ABOUT THE SUBJECT.THEIR ARE ALOT OF PEOPLE THAT HAVE BEEN USING COMFREY FOR GENERATIONS BUT I NOTICE THAT THESE GREAT SCIENTIST NEVER DID STUDYS ON THESE FAMILYS TO SEE THE EFFECTS OR EVEN TESTED THE ANIMALS OF SAID FAMILYS THAT ALSO ARE FED COMFREY, NO INSTEAD THEY TEST BABY RATS BY INJECTING THE RATS WITH THE ONE CHEMICAL THAT IS SAID TO BE THE CULPRIT AND THEY INJECT LARGE AMOUNTS.THAT DOESNT SOUND VERY SCIENTIFIC.AND BY THE WAY MY FAMILY IS ONE OF THOSE FAMILIES THAT THOSE SO CALLED SCIENTIST SHOULD OF TESTED OUR FAMILY HAS BEEN USING COMFREY FOR AT LEAST 9 GENERATIONS ON BOTH OURSELVES AND OUR FARM ANIMALS AND NO ONE IN OUR FAMILY HAS DIED FROM CANCER OR HAD CANCER.BUT LIKE I SAID I'M NOT A SCIENTIST I ONLY HAVE PERSONAL AND FAMILIAL AND FAMILY FREINDS EXPERIENCE WITH THIS HERB.

Joy: that's nice. Now 1) go re-read the bit about liver damage (which isn't cancer), 2) re-read the bit where it says that yep, the plant itself (not a single constituent) causes liver damage in people (which aren't mice), and 3) fix your caps-lock key. Thanks.

SORRY I FORGOT TO MENTION THE LIVER DAMAGE.BUT SAME THING IF COMFREY IS SO DANGEROUS WHY IS IT THAT NO ONE I KNOW OR HAVE HEARD FROM THAT USES COMFREY HAS EVER HAD A PROBLEM FROM IT.ARE WE JUST THE BLESSED MULTITUDE THAT CAN CONSUME SUCH A DANGEROUS HERB AND NOT HAVE ADVERSE REACTIONS.WHY HASNT THESE SCIENTIST BEEN ABLE TO EXPLAIN ALL THE PEOPLE THAT USE THIS HERB AND HAVE USED IT FOR YEARS WITH NO HEALTH PROBLEMS.ALSO WHY HAVE I NEVER SEEN A BLOG AGAINST COMFREY FROM ANYONE WHO HAS HAD THESE ADVERSE REACTIONS.IT SEEMS ODD THAT THESE PEOPLE NEVER SEEM TO BE TELLING THE WORLD ABOUT THESE DANGERS.YOU ONLY HEAR THE NEGATIVE STUFF FROM THESE OBSCUR SCIENTIST THAT SUPPOSE TO OF DONE THESE IN DEPTH TEST.IT JUST SEEMS FUNNY HOW SUCH A WIDELY USED HERB THAT HAS BEEN AROUND FOR HUNDREDS OF YEARS IS NOW SUPPOSED TO BE CAUSING ALL THESE HEALTH PROBLEMS AND HAS EVEN BEEN LABLED AS POSION IN SOME PLACES YET NO ONE THAT I HAVE MEET OR TALKED TO ON THE NET THAT HAS USED THIS HERB HAS HAD ANY LIVER PROBLEMS OR CANCERS OR ANYTHING LIKE THAT.AND LIKE I SAID BEFORE MY FAMILY HAS BEEN USING THIS HERB FOR 9 GENERATIONS AND WE ARE A VERY HEALTHY BUNCH AND QUITE A LARGE FAMILY.I JUST THINK THERE ARE TWO SIDES TO EVERY COIN AND TO TAKE A FEW SCIENTIST WORDS AS LAW SEEMS KINDA SILLY WITHOUT MORE IN DEPTH TEST.MABYE IF THESE PEOPLE CAN ANSWER SOME OF THE QUESTIONS AND EXPLAIN ALL THE HEALTHY ANIMALS AND PEOPLE THAT USE THIS HERB WITH NO ILL EFFECTS I MIGHT TRUST WHAT THIER SAYING MORE.
OH AND SORRY FOR ALL THE CAPS BUT MY CAPS LOCK BUTTON IS STUCK AND IT WONT UNLOCK.

Comfrey is INSIDIOUS. You don't even know that it has severely damaged your liver... and then you die.
So, how many liver autopsies have been done on your 9 generations of family? And how many liver biopsies?
Because you cannot say that it hasn't killed anybody (by destroying their liver) UNLESS you have checked the liver. Before or after death -- it doesn't really matter which you chose.

OK I DONT KNOW WHERE YOU GET YOUR INFORMATION BUT WHOEVER TOLD YOU THAT YOU CAN DIE FROM LIVER DISEASE WITHOUT KNOWING IT IS AN IDIOT,YOUR LIVER IS A MAJOR ORGAN AND IF SOMTHING IS WRONG WITH IT THERE ARE SIGNS /SYMPTOMS.ONE VERY WELL KNOWN SIGN IS JUNDICE BUT THERE ARE ALOT OF OTHER SIGNS AND YOU DONT NEED A BIOPSY TO KNOW THERE IS SOMETHING WRONG WITH YOUR LIVER.THERE ARE BLOOD TEST AND ULTRA SOUNDS.CAT SCANS AND MRIS WILL ALSO SHOW LIVER DISEASE.THE ONLY WAY YOU WOULDNT KNOW YOU HAVE SOMETHING WRONG WITH YOUR LIVER IS IF YOU DONT GO TO A DOCTOR.AND YES I HAVE HAD A LIVER FUNCTION TEST (WHICH IS A BLOOD TEST JUST SO YOU KNOW)AND IT WAS FINE.LIVER DAMAGE CAN BE CAUGHT BY A COMPENTENT DOCTOR WAY BEFORE IT WOULD KILL YOU.ALSO I BELEIVE I MENTION BEFORE THAT MY FAMILY HAS BEEN TAKEN COMFREY FOR AT LEAST 9 GENERATIONS AND THE YOUNGEST PERSON IN OUR FAMILY THAT DIED OF NATURAL CAUSES WAS 89 YRS OLD AND SHE WAS QUITE ACTIVE AND HEALTHY ALL THE WAY UP TO HER DEATH.WHICH SHE WOULDNT HAVE BEEN IF SHE HAD LIVER DISEASE.AS I SAID BEFORE NO ONE IN MY FAMILY HAS HAD LIVER PROBLEMS.WELL EXCEPT ONE WHO HAD HEP C.BUT OF COURSE THAT HAS NOTHING TO DO WITH COMFREY.

1) congratulations on knowing a) what your family has eaten for 9 generations back, and 2) what they died of for 9 generations back. That's quite a feat, and I expect you're really really old...
2) I've seen lots of people with severe liver damage, with NO jaundice, at all. Try pretty much anybody with chronic Hep B for starters. Hep B is a killer ... Hep C didn't show jaundice, either, in the ones I've seen.

I fully agree with Joy. The fact of the matter is that the medical mafia is spreading misinformation about the herb because of its treatment of cancer. We can't have an herb curing cancer. There's a lot of money to be lost. I have read some of the info concerning all those supposed tests they've made. It's all inconclusive. Anyone who has an understanding of herbs, which by the way, you don't, henriette, would know that hepatitis, any variation of it, s curable, and therefore would nevcer post a remark such as the one I am reading here.

Oooh. A full-out flame, complete with a personal attack!
1) Yes, people have in fact had liver transplants because of comfrey. There's nothing inconclusive about it.
2) while I applaud your attack on the medical mainstream, you're unfortunately not helping herbs any - because comfery is livertoxic, not "withheld by the medical mafia".
3) You'll have to shout louder if you want people to actually believe that I don't understand herbs. Really. You're so far off the mark that your remark makes me smirk, not frown.
4) Do read up on hepatitis B -- and its incurability -- there's a good Lana. Yes, I've seen one (1) confirmed hep B completely disappear on a liver biopsy, after decades of disease. That is, however, extraordinary, and nothing you can count on for your general run-of-the-mill hep B. It's still, for all practical purposes, incurable.



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